A photon and an electron have energy 200 eV each. Which one of these has greater de-Broglie wavelength ?

Explanation

To determine which has a greater de-Broglie wavelength between a photon and an electron, both having an energy of 200 eV, we will follow these steps:

### Step 1: Understand the de-Broglie wavelength formula
The de-Broglie wavelength (λ) is given by the formula:
\[ \lambda = \frac{h}{p} \]
where \( h \) is Planck's constant and \( p \) is the momentum.
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